This project was initiated in LBC to provide specialized mass spectrometry analysis, primarily but not exclusively of trace organic compounds isolated from biological systems. Over the past year, an Ion-Trap mass spectrometer and a Fourier Transform Infrared spectrometer have been introduced as invaluable tools for the routine use of laboratory personnel. A new high resolution mass spectrometer is currently being evaluated in order to provide high resolution gas chromatographic and peptide analysis. The joint development with LC, NHLBI, of Californium plasma desorption and Ion-Trap mass spectrometers for analysis of non-volatile high molecular weight compounds and complex natural products has provided invaluable new approaches to characterization of such compounds. Identification of pheromones from the skin of various snakes provides the basis for possible development of repellents and/or attractants for harmful snake species. The countercurrent chromatograph mass spectrometry interface has been adapted for trace component separations. Mass spectrometry has been utilized for the structural identification of a variety of biologically active marine natural products from South Pacific. Samples for mass spectral analysis derive from many facilities and researchers outside LBC.